Celltrion

Approval of 45mg/0.5mL solution in a single-dose vial for subcutaneous injection expands dosing flexibility for pediatric patients with plaque psoriasis (PsO) or psoriatic arthritis (PsA) under 60kgThe FDA previously approved STEQEYMA® 45mg/0.5mL, 90mg/mL in a single-dose prefilled syringe for subcutaneous injection, and 130mg/26mL in a single-dose vial for intravenous infusion in December 2024STEQEYMA now matches all dosage forms and strengths of its reference product, STELARA® INCHEON, South Korea, June 15, 2025 -- Celltrion, Inc. today announced that the U.S. Food and Drug Administration (FDA) has approved a new presentation of STEQEYMA® (ustekinumab-stba), a biosimilar to STELARA® (ustekinumab), in a 45mg/0.5mL solution in a single-dose vial for subcutaneous injection. The additional presentation is approved for the treatment of pediatric patients aged 6 to 17 years, weighing less than 60kg, with plaque psoriasis (PsO) or psoriatic arthritis (PsA).[1] With this approval, STEQEYMA now offers all dosage forms and strengths of its reference product, providing flexibility to meet physicians' clinical needs while supporting treatment continuity for patients. In December 2024, the FDA approved STEQEYMA in 45mg/0.5mL and 90mg/mL solutions in a single-dose prefilled syringe for subcutaneous injection, and 130mg/26mL in a single-dose vial for intravenous infusion in adult and pediatric patients 6 years and older with plaque psoriasis and psoriatic arthritis, as well as adult patients with Crohn's disease and ulcerative colitis. "Managing inflammatory diseases in pediatric patients can be particularly complex," said Hetal Patel, PharmD MBA, Vice President of Medical Affairs at Celltrion USA. "The new dosage form and strength of STEQEYMA allow us to better meet the specific needs of young patients, giving physicians a valuable treatment option with flexibility, supported by a well-established safety and efficacy profile." "We are proud to offer a new presentation of STEQEYMA that aligns with the indications of the reference product," said Thomas Nusbickel, Chief Commercial Officer at Celltrion USA. "This approval reinforces our commitment to broadening access for all patient populations, including children aged 6 years and older living with chronic inflammatory conditions. As a company with a strong legacy in immunology, we are dedicated to ensuring broader access and flexibility in care for patients of all ages." The FDA approval of STEQEYMA was based on the totality of evidence, including the results from a phase III study in adults with moderate to severe plaque psoriasis, in which the primary endpoint was the rate of change in the Psoriasis Area and Severity Index (PASI) for skin symptoms. The clinical results demonstrated that STEQEYMA and its reference product, ustekinumab, are highly similar, and have no clinically meaningful differences in terms of safety and efficacy.[2],[3] The FDA has granted STEQEYMA full interchangeability with STELARA across all indications of STELARA, following the expiration of exclusivity for the first interchangeable biosimilar on April 30, 2025. Notes to Editors: About STEQEYMA® (ustekinumab-stba) STEQEYMA®, formerly known as CT-P43, is a human IL-12 and -23 antagonist indicated for multiple immune-mediated diseases. It encompasses all indications approved for the STELARA® reference product, including psoriasis (PsO), psoriatic arthritis (PsA), Crohn's disease (CD), ulcerative colitis (UC) in adults, and PsO and PsA in pediatric patients 6 years of age and older. STEQEYMA is available in both subcutaneous and intravenous formulations. The subcutaneous injection comes in 45mg/0.5 mL or 90mg/1 mL solution in a single-dose, prefilled syringe and 45mg/0.5mL solution in a single-dose vial. The intravenous infusion is provided as a 130mg/26 mL (5mg/mL) solution in a single-dose vial. INDICATIONS STEQEYMA® (ustekinumab-stba) is indicated for the treatment of: Plaque Psoriasis (PsO) in adults and pediatric patients 6 years of age and older with moderate to severe plaque psoriasis who are candidates for phototherapy or systemic therapy.Psoriatic Arthritis (PsA) in adults and pediatric patients 6 years of age and older with active psoriatic arthritis.Crohn's Disease (CD) in adult patients with moderately to severely active Crohn's disease.Ulcerative Colitis (UC) in adult patients with moderately to severely active ulcerative colitis. IMPORTANT SAFETY INFORMATION STEQEYMA is contraindicated in patients with clinically significant hypersensitivity to ustekinumab products or to any of the excipients in STEQEYMASerious infections have occurred. Avoid starting STEQEYMA during any clinically important active infection. If a serious or clinically significant infection develop, discontinue STEQEYMA until the infection resolves.Serious infections from mycobacteria, salmonella, and BCG vaccinations have been reported in patients genetically deficient in IL-12/IL-23. Consider diagnostic tests for these infections as dictated by clinical circumstances.Evaluate patients for TB prior to starting STEQEYMA. Initiate treatment of latent TB before administering STEQEYMA.Ustekinumab products may increase risk of malignancy. The safety of ustekinumab products in patients with a history of or a known malignancy has not been evaluated. Monitor all patients receiving STEQEYMA for signs of malignancies.If an anaphylactic or other clinically significant hypersensitivity reaction occurs, institute appropriate therapy and discontinue STEQEYMA.If Posterior Reversible Encephalopathy Syndrome (PRES) is suspected, treat promptly, and discontinue STEQEYMA.Avoid use of live vaccines in patients during treatment with STEQEYMA. Non-live vaccinations received during STEQEYMA treatment may not elicit enough immune response to prevent disease.If diagnosis of noninfectious pneumonia is confirmed, discontinue STEQEYMA and institute appropriate treatment.The most common adverse reactions (≥3%) reported in patients receiving ustekinumab were:Psoriasis: nasopharyngitis, upper respiratory tract infection, headache, and fatigue.CD: vomiting, nasopharyngitis, injection site erythema, vulvovaginal candidiasis/mycotic infection, bronchitis, pruritus, urinary tract infection, and sinusitis.UC: nasopharyngitis, headache, abdominal pain, influenza, fever, diarrhea, sinusitis, fatigue, and nausea. For more information, see Full Prescribing Information. About Celltrion, Inc.Celltrion is a leading biopharmaceutical company that specializes in researching, developing, manufacturing, marketing and sales of innovative therapeutics that improve people's lives worldwide. Celltrion is a pioneer in the biosimilar space, having launched the world's first monoclonal antibody biosimilar. Our global pharmaceutical portfolio addresses a range of therapeutic areas including immunology, oncology, hematology, ophthalmology and endocrinology. Beyond biosimilar products, we are committed to advancing our pipeline with novel drugs to push the boundaries of scientific innovation and deliver quality medicines. For more information, please visit our website www.celltrion.com/en-us. and stay updated with our latest news and events on our social media: LinkedIn, Instagram, X, and Facebook. About Celltrion USACelltrion USA is Celltrion's U.S. subsidiary established in 2018. Headquartered in New Jersey, Celltrion USA is committed to expanding access to innovative biologics to improve care for U.S. patients. Celltrion's FDA-approved biosimilar products in immunology, oncology, hematology, and endocrinology include: INFLECTRA® (infliximab-dyyb), TRUXIMA® (rituximab-abbs), HERZUMA® (trastuzumab-pkrb), VEGZELMA® (bevacizumab-adcd), YUFLYMA®(adalimumab-aaty), AVTOZMA® (tocilizumab-anho), STEQEYMA® (ustekinumab-stba), STOBOCLO® (denosumab-bmwo), OSENVELT® (denosumab-bmwo) and OMLYCLO® (omalizumab-igec), as well as the novel biologic ZYMFENTRA® (infliximab-dyyb). Celltrion USA will continue to leverage Celltrion's unique heritage in biotechnology, supply chain excellence and best-in-class sales capabilities to improve access to high-quality biopharmaceuticals for U.S. patients. For more information, please visit www.celltrionusa.com and stay updated with our latest news and events on our social media: LinkedIn. FORWARD-LOOKING STATEMENT Certain information set forth in this press release contains statements related to our future business and financial performance and future events or developments involving Celltrion, Inc. and its subsidiaries that may constitute forward-looking statements under pertinent securities laws. This press release contains forward looking statements. These statements may be also identified by words such as "prepares", "hopes to", "upcoming", "plans to", "aims to", "to be launched", "is preparing", "once gained", "could", "with the aim of", "may", "once identified", "will", "working towards", "is due", "become available", "has potential to", "anticipate" the negative of these words or such other variations thereon or comparable terminology. In addition, our representatives may make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Celltrion, Inc. and its subsidiaries' management, of which many are beyond its control. Forward-looking statements are provided to allow potential investors the opportunity to understand management's beliefs and opinions in respect of the future so that they may use such beliefs and opinions as one factor in evaluating an investment. These statements are not guarantees of future performance and undue reliance should not be placed on them. Such forward-looking statements necessarily involve known and unknown risks and uncertainties associated with the company's business, including the risk factors disclosed in its Annual Report and/or Quarterly Reports, which may cause actual performance and financial results in future periods to differ materially from any projections of future performance or results expressed or implied by such statements. Celltrion, Inc. and its subsidiaries undertake no obligation to update forward-looking statements if circumstances or management's estimates or opinions should change except as required by applicable securities laws. Trademarks STELARA® is a registered trademark of Johnson & Johnson.STEQEYMA® is a registered trademark of Celltrion, Inc., used under license. References [1] STEQEYMA U.S. prescribing information (2025)[2] Papp KA et al., Efficacy and Safety of Candidate Biosimilar CT-P43 Versus Originator Ustekinumab in Moderate to Severe Plaque Psoriasis: 28-Week Results of a Randomised, Active-Controlled, Double-Blind, Phase III study. BioDrugs. 2023; Online ahead of print. Available at: https://link.springer.com/article/10.1007/s40259-023-00630-5#article-info [Last accessed June 2025][3] Papp K et al., Efficacy and Safety after Switch from Reference Ustekinumab to Ustekinumab Biosimilar (CT-P43) in comparison with the Maintenance Group (CTP43 or Reference Ustekinumab) in Patients with Moderate-to-Severe Plaque Psoriasis: 1-Year Result. [EADV 2023, Abstract #4035]. Available at: https://eadv.org/wp-content/uploads/scientific-abstracts/EADV-congress-2023/Biologics-immunotherapy-targeted-therapy.pdf [Last accessed June 2025]

YUFLYMA® (adalimumab-aaty) is a high-concentration (100mg/mL) and citrate-free formulation of Humira® (adalimumab) biosimilar[1]Celltrion previously received interchangeability (IC) designation for YUFLYMA® (adalimumab-aaty) in prefilled syringes (20mg & 80mg); Expanded interchangeability (IC) designation applies to prefilled syringe (40mg) and autoinjectors (40mg and 80mg)  INCHEON, South Korea, May 23, 2025 /-- Celltrion, Inc. today announced that the U.S. Food and Drug Administration (FDA) has granted an expanded interchangeable designation for YUFLYMA® (adalimumab-aaty), now including prefilled syringe (40mg) and autoinjectors (40mg and 80mg) presentations. With this approval, YUFLYMA is now fully interchangeable with the reference product, Humira® (adalimumab), across all marketed dosage forms and strengths. YUFLYMA is a high-concentration, citrate-free biosimilar to Humira, approved for multiple inflammatory indications including rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), ulcerative colitis (UC), plaque psoriasis (Ps), hidradenitis suppurativa (HS), and uveitis (UV) in adult patients; Crohn's disease (CD) in adults and pediatric patients 6 years of age and older; and juvenile idiopathic arthritis (JIA) in patients 2 years of age and older.[1]  "This full interchangeability designation comes at a pivotal time as Celltrion continues to lead in the evolving biosimilar landscape," said Thomas Nusbickel, Chief Commercial Officer at Celltrion USA. “YUFLYMA – a high-concentration, citrate-free adalimumab biosimilar now fully interchangeable with Humira – reflects our long-standing commitment to delivering high-quality, accessible treatment options. Going forward, Celltrion will continue to put patients first by keeping drug costs affordable and remaining at the forefront of the U.S. biosimilar market, bringing competitive pricing and high-quality, accessible treatment options.” The interchangeable designation builds on the Phase III interchangeability study, which demonstrated similar outcomes in terms of pharmacokinetics, efficacy, safety and immunogenicity in patients with moderately to severely active plaque psoriasis who received reference adalimumab (ADA) continuously and those who alternated between reference ADA and YUFLYMA during the dosing interval of Weeks 25-27. The result of the interchangeability study was presented at the European Academy of Dermatology & Venereology (EADV), September 2024, in the Netherlands.[2] YUFLYMA was first introduced in the U.S. market in July 2023 and is currently available as a 20mg, 40mg, and 80mg solution for injection in prefilled syringes and as 40mg and 80mg in autoinjectors. Celltrion offers adalimumab-aaty in both branded and unbranded versions, with two pricing options to meet different patient needs and improve patient affordability.  Notes to Editors: About YUFLYMA® (CT-P17, biosimilar adalimumab-aaty)[1] YUFLYMA is a high-concentration, low-volume and citrate-free adalimumab biosimilar to receive European Commission approval. YUFLYMA is FDA approved for the treatment of patients with rheumatoid arthritis, juvenile idiopathic arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, ulcerative colitis, plaque psoriasis, hidradenitis suppurativa and uveitis. YUFLYMA has been designated by the FDA as an interchangeable biosimilar in a prefilled syringe and autoinjector. YUFLYMA is a recombinant fully human anti–tumor necrosis factor α (anti-TNFα) monoclonal antibody. YUFLYMA is available in prefilled syringe as 20mg/0.2mL, 40mg/0.4mL and 80mg/0.8mL and autoinjector as 40mg/0.4mL and 80mg/0.8mL. Additionally, YUFLYMA features one of the longest shelf lives in its class, maintaining stability at room temperature (77 °F, 25 °C) for up to 31 days. IMPORTANT SAFETY INFORMATION[1]This important safety information also applies to YUFLYMA® (adalimumab-aaty). SERIOUS INFECTIONS Patients treated with adalimumab-aaty are at increased risk for developing serious infections that may lead to hospitalization or death. Most patients who developed these infections were taking concomitant immunosuppressants such as methotrexate or corticosteroids. Discontinue adalimumab-aaty if a patient develops a serious infection or sepsis. Reported infections include: Active tuberculosis (TB), including reactivation of latent TB. Patients with TB have frequently presented with disseminated or extrapulmonary disease. Test patients for latent TB before adalimumab-aaty use and during therapy. Initiate treatment for latent TB prior to adalimumab-aaty use.Invasive fungal infections, including histoplasmosis, coccidioidomycosis, candidiasis, aspergillosis, blastomycosis, and pneumocystosis. Patients with histoplasmosis or other invasive fungal infections may present with disseminated, rather than localized, disease. Antigen and antibody testing for histoplasmosis may be negative in some patients with active infection. Consider empiric antifungal therapy in patients at risk for invasive fungal infections who develop severe systemic illness.Bacterial, viral, and other infections due to opportunistic pathogens, including Legionella and Listeria. Carefully consider the risks and benefits of treatment with adalimumab-aaty prior to initiating therapy in patients with chronic or recurrent infection. Monitor patients closely for the development of signs and symptoms of infection during and after treatment with adalimumab-aaty, including the possible development of TB in patients who tested negative for latent TB infection prior to initiating therapy. Treatment with adalimumab-aaty should not be initiated in patients with an active infection, including localized infections.Patients over 65 years of age, patients with co-morbid conditions and/or patients taking concomitant immunosuppressants (such as corticosteroids or methotrexate), may be at greater risk of infection. Discontinue adalimumab-aaty if a patient develops a serious infection or sepsis. For a patient who develops a new infection during treatment with adalimumab-aaty, closely monitor them, perform a prompt and complete diagnostic workup appropriate for an immunocompromised patient, and initiate appropriate antimicrobial therapy.Drug interactions with biologic products: In clinical studies in patients with RA, an increased risk of serious infections has been observed with the combination of TNF blockers with anakinra or abatacept, with no added benefit; therefore, use of adalimumab-aaty with abatacept or anakinra is not recommended in patients with RA. A higher rate of serious infections has also been observed in patients with RA treated with rituximab who received subsequent treatment with a TNF blocker. There is insufficient information regarding the concomitant use of adalimumab-aaty and other biologic products for the treatment of RA, PsA, AS, CD, UC, PS, and HS. Concomitant administration of adalimumab-aaty with other biologic disease-modifying antirheumatic drugs (DMARDs) (e.g., anakinra and abatacept) or other TNF blockers is not recommended based upon the possible increased risk for infections and other potential pharmacological interactions. A higher rate of serious infections has been observed in RA patients treated with rituximab who received subsequent treatment with a TNF blocker. MALIGNANCY Lymphoma and other malignancies, some fatal, have been reported in children and adolescent patients treated with TNF blockers, including adalimumab products. Postmarketing cases of hepatosplenic T-cell lymphoma (HSTCL), a rare type of T-cell lymphoma, have been reported in patients treated with TNF blockers, including adalimumab products. These cases have had a very aggressive disease course and have been fatal. The majority of reported TNF blocker cases have occurred in patients with Crohn's disease or ulcerative colitis and the majority were in adolescent and young adult males. Almost all of these patients had received treatment with azathioprine or 6-mercaptopurine concomitantly with a TNF blocker at or prior to diagnosis. It is uncertain whether the occurrence of HSTCL is related to the use of a TNF blocker or a TNF blocker in combination with these other immunosuppressants. Consider the risks and benefits of TNF blocker treatment including adalimumab-aaty prior to initiating therapy in patients with a known malignancy other than a successfully treated non-melanoma skin cancer (NMSC), or when considering continuing a TNF blocker in patients who develop a malignancy.In controlled portions of clinical trials of some adalimumab products, more cases of malignancies have been observed compared to control-treated adult patients.NMSC was reported during clinical trials for patients treated with adalimumab products. During the controlled portions of 39 global adalimumab clinical trials in adult patients with RA, PsA, AS, CD, UC, PS, HS and UV, the rate (95% confidence interval) of NMSC was 0.8 (0.52, 1.09) per 100 patient-years among adalimumab-treated patients and 0.2 (0.10, 0.59) per 100 patient-years among control-treated patients. Examine all patients, particularly those with a medical history of prior prolonged immunosuppressant therapy or psoriasis patients with a history of psoralen + ultraviolet light A (PUVA) treatment, for the presence of NMSC prior to and during treatment with adalimumab-aaty.In clinical trials of some adalimumab products, there was an approximately threefold higher rate of lymphoma than expected in the general U.S. population. Patients with RA and other chronic inflammatory diseases, particularly those with highly active disease and/or chronic exposure to immunosuppressant therapies, may be at a higher risk (up to severalfold) than the general population for the development of lymphoma, even in the absence of TNF blockers.Postmarketing cases of acute and chronic leukemia were reported with the use of a TNF blocker in RA and other indications. Approximately half of the postmarketing cases of malignancies in children, adolescents, and young adults receiving adalimumab were lymphomas; other cases represented a variety of different malignancies and included rare malignancies usually associated with immunosuppression and malignancies that are not usually observed in children and adolescents. HYPERSENSITIVITY Anaphylaxis and angioneurotic edema have been reported following administration of adalimumab products. If an anaphylactic or other serious allergic reaction occurs, immediately discontinue administration of adalimumab-aaty and institute appropriate therapy. HEPATITIS B VIRUS REACTIVATION Use of TNF blockers, including adalimumab-aaty, may increase the risk of reactivation of hepatitis B virus (HBV) in patients who are chronic carriers. In some instances, HBV reactivation occurring in conjunction with TNF blocker therapy has been fatal.Evaluate patients at risk for HBV infection for prior evidence of HBV infection before initiating TNF blocker therapy.Exercise caution in prescribing TNF blockers for patients identified as carriers of HBV and closely monitor such patients for clinical and laboratory signs of active HBV infection throughout therapy and for several months following termination of therapy.In patients who develop HBV reactivation, stop adalimumab-aaty and initiate effective antiviral therapy with appropriate supportive treatment. The safety of resuming TNF blocker therapy after HBV reactivation is controlled is not known. Therefore, exercise caution when considering resumption of adalimumab-aaty therapy in this situation and monitor patients closely. NEUROLOGIC REACTIONS Use of TNF blocking agents, including adalimumab products, has been associated with rare cases of new onset or exacerbation of clinical symptoms and/or radiographic evidence of central nervous system demyelinating disease, including multiple sclerosis (MS) and optic neuritis, and peripheral demyelinating disease, including Guillain-Barré syndrome.Exercise caution in considering the use of adalimumab-aaty in patients with preexisting or recent-onset central or peripheral nervous system demyelinating disorders; discontinuation of adalimumab-aaty should be considered if any of these disorders develop.There is a known association between intermediate uveitis and central demyelinating disorders. HEMATOLOGIC REACTIONS Rare reports of pancytopenia including aplastic anemia have been reported with TNF blocking agents.Adverse reactions of the hematologic system, including medically significant cytopenia, have been infrequently reported with adalimumab products.Consider discontinuation of adalimumab-aaty therapy in patients with confirmed significant hematologic abnormalities. HEART FAILURE Cases of worsening congestive heart failure (CHF) and new-onset CHF have been reported with TNF blockers. Cases of worsening CHF have also been observed with adalimumab products.Exercise caution when using adalimumab-aaty in patients who have heart failure and monitor them carefully. AUTOIMMUNITY Treatment with adalimumab products may result in the formation of autoantibodies and, rarely, in the development of a lupus-like syndrome. If a patient develops symptoms suggestive of a lupus-like syndrome following treatment with adalimumab-aaty, discontinue treatment. IMMUNIZATIONS Patients on adalimumab-aaty may receive concurrent vaccinations, except for live vaccines.It is recommended that pediatric patients, if possible, be brought up to date with all immunizations in agreement with current immunization guidelines prior to initiating adalimumab-aaty therapy.No data are available on the secondary transmission of infection by live vaccines in patients receiving adalimumab products.The safety of administering live or live-attenuated vaccines in infants exposed to adalimumab in utero is unknown. Risks and benefits should be considered prior to vaccinating (live or live-attenuated) exposed infants. ADVERSE REACTIONS The most common adverse reactions in adalimumab clinical trials (>10%) were infections (e.g., upper respiratory, sinusitis), injection site reactions, headache, and rash. INDICATIONS Adalimumab-aaty is a tumor necrosis factor (TNF) blocker indicated for: Rheumatoid Arthritis (RA): reducing signs and symptoms, inducing major clinical response, inhibiting the progression of structural damage, and improving physical function in adult patients with moderately to severely active RAJuvenile Idiopathic Arthritis (JIA): reducing signs and symptoms of moderately to severely active polyarticular JIA in patients 2 years of age and olderPsoriatic Arthritis (PsA): reducing signs and symptoms, inhibiting the progression of structural damage, and improving physical function in adult patients with active PsAAnkylosing Spondylitis (AS): reducing signs and symptoms in adult patients with active ASCrohn's Disease (CD): treatment of moderately to severely active Crohn's disease in adults and pediatric patients 6 years of age and olderUlcerative Colitis (UC): treatment of moderately to severely active ulcerative colitis in adults Limitations of Use: Effectiveness has not been established in patients who have lost response to or were intolerant to TNF blockersPlaque Psoriasis (Ps): treatment of adult patients with moderate to severe chronic plaque psoriasis who are candidates for systemic therapy or phototherapy, and when other systemic therapies are medically less appropriateHidradenitis Suppurativa (HS): treatment of adult patients with moderate to severe hidradenitis suppurativaUveitis (UV): treatment of non-infectious intermediate, posterior, and panuveitis in adult patients For Yuflyma (adalimumab-aaty): Please click for Full U.S. Prescribing Information. For adalimumab-aaty: Please see Full U.S. Prescribing Information. Globally, prescribing information varies; refer to the individual country product label for complete information. About Celltrion, Inc. Celltrion is a leading biopharmaceutical company that specializes in researching, developing, manufacturing, marketing and sales of innovative therapeutics that improve people's lives worldwide. Celltrion is a pioneer in the biosimilar space, having launched the world's first monoclonal antibody biosimilar. Our global pharmaceutical portfolio addresses a range of therapeutic areas including immunology, oncology, hematology, ophthalmology and endocrinology. Beyond biosimilar products, we are committed to advancing our pipeline with novel drugs to push the boundaries of scientific innovation and deliver quality medicines. For more information, please visit our website www.celltrion.com/en-us  and stay updated with our latest news and events on our social media: LinkedIn, Instagram, X, and Facebook. About Celltrion USA Celltrion USA is Celltrion's U.S. subsidiary established in 2018. Headquartered in New Jersey, Celltrion USA is committed to expanding access to innovative biologics to improve care for U.S. patients. Celltrion's FDA-approved biosimilar products in immunology, oncology, hematology, and endocrinology include: INFLECTRA® (infliximab-dyyb), TRUXIMA® (rituximab-abbs), HERZUMA® (trastuzumab-pkrb), VEGZELMA® (bevacizumab-adcd), YUFLYMA®(adalimumab-aaty), AVTOZMA® (tocilizumab-anho), STEQEYMA® (ustekinumab-stba), STOBOCLO® (denosumab-bmwo), OSENVELT® (denosumab-bmwo) and OMLYCLO® (omalizumab-igec), as well as the novel biologic ZYMFENTRA® (infliximab-dyyb). Celltrion USA will continue to leverage Celltrion's unique heritage in biotechnology, supply chain excellence and best-in-class sales capabilities to improve access to high-quality biopharmaceuticals for U.S. patients. For more information, please visit www.celltrionusa.com and stay updated with our latest news and events on LinkedIn. FORWARD-LOOKING STATEMENT Certain information set forth in this press release contains statements related to our future business and financial performance and future events or developments involving Celltrion, Inc. and its subsidiaries that may constitute forward-looking statements under pertinent securities laws. This press release contains forward looking statements. These statements may be also identified by words such as "prepares", "hopes to", "upcoming", "plans to", "aims to", "to be launched", "is preparing", "once gained", "could", "with the aim of", "may", "once identified", "will", "working towards", "is due", "become available", "has potential to", "anticipate" the negative of these words or such other variations thereon or comparable terminology. In addition, our representatives may make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Celltrion, Inc. and its subsidiaries' management, of which many are beyond its control. Forward-looking statements are provided to allow potential investors the opportunity to understand management's beliefs and opinions in respect of the future so that they may use such beliefs and opinions as one factor in evaluating an investment. These statements are not guarantees of future performance and undue reliance should not be placed on them. Such forward-looking statements necessarily involve known and unknown risks and uncertainties associated with the company's business, including the risk factors disclosed in its Annual Report and/or Quarterly Reports, which may cause actual performance and financial results in future periods to differ materially from any projections of future performance or results expressed or implied by such statements. Celltrion, Inc. and its subsidiaries undertake no obligation to update forward-looking statements if circumstances or management's estimates or opinions should change except as required by applicable securities laws. Trademarks Humira is a registered trademark of AbbVie.YUFLYMA® is a registered trademark of Celltrion, Inc., used under license. References[1] YUFLYMA US prescribing information (2023)[2] Lebwohl M et al., Pharmacokinetics, Efficacy and Safety after Multiple Switches from Reference Adalimumab to Adalimumab Biosimilar (CT-P17) in comparison with the Maintenance Group (Reference Adalimumab) in Patients with Moderate-toSevere Plaque Psoriasis: Week 27 Results from the Phase III Interchangeability Study. [EADV 2024, Poster number P0931]. Available at:https://s3.eu-central-1.amazonaws.com/m-anage.com.storage.eadv/abstracts_congress_2024/41489.pdf

Six abstracts accepted for presentation includes post hoc analyses and real-world evidence for ZYMFENTRA® (infliximab-dyyb)Findings reinforce clinical decision-making in long-term management of moderate-to-severe Crohn's disease and ulcerative colitis and underscore Celltrion's commitment to advancing scientific understanding in the field of IBD INCHEON, South Korea, April 28, 2025 -- Celltrion, Inc. today announced that six abstracts will be presented at the 2025 Digestive Disease Week® (DDW) Annual Meeting, taking place May 3-6 in San Diego, California. The oral and poster presentations will feature data including post hoc analyses of its pivotal LIBERTY studies (LIBERTY-CD and LIBERTY-UC) of ZYMFENTRA®, the first and only FDA-approved subcutaneous infliximab. "We are excited by the opportunity to present further analyses reinforcing ZYMFENTRA's clinical value for HCPs and patients," said Hetal Patel, PharmD MBA, Vice President of Medical Affairs at Celltrion USA. "With IBD management becoming increasingly individualized, we anticipate these analyses will help clarify how ZYMFENTRA performs across a wide range of patient types, from long-term drug persistence to recapture following dose escalation." The presentations reflect Celltrion's continued commitment to making comprehensive clinical and real-world evidence accessible to healthcare professionals in the U.S., supporting informed treatment decisions in a complex and evolving IBD landscape. The details of Celltrion's abstract presentations are as follows:Abstract TitlePresentation DetailsAll times PDTEndoscopic and histologic outcomes in patientswith moderate-to-severe ulcerative colitis treatedwith subcutaneous infliximab: A post hoc analysisof the LIBERTY-UC study Poster Presentation #0035IMIBD_POS: IBD: Controlled Clinical Trials in HumansSunday May 4, 2025 / 12:30-13:30 Time to clinical recapture after dose escalation ofsubcutaneous infliximab following loss ofresponse: A post hoc analysis of the 2-year Phase3 LIBERTY-CD & LIBERTY-UC trials Poster Presentation #0016IMIBD_POS: IBD: Controlled Clinical Trials in HumansSunday May 4, 2025 / 12:30-13:30 Efficacy of subcutaneous infliximab maintenancetherapy according to disease location in patientswith moderate-to-severe Crohn's disease: A posthoc analysis of the Phase 3 LIBERTY-CD study Poster Presentation #0039IMIBD_POS: IBD: Controlled Clinical Trials in HumansSunday May 4, 2025 / 12:30-13:30 Impact of immunogenicity on 2-year clinicaloutcomes in patients with moderate-to-severeCrohn's disease treated with subcutaneousinfliximab: A post hoc analysis of the Phase 3LIBERTY-CD study Poster Presentation #0011IMIBD_POS: IBD: Controlled Clinical Trials in HumansSunday May 4, 2025 / 12:30-13:30 Characterization of patients who experience lossof response during maintenance treatment withsubcutaneous infliximab: A post hoc analysis ofthe 2-year Phase 3 LIBERTY-CD & LIBERTY-UCtrials Poster Presentation #0017IMIBD_POS: IBD: Controlled Clinical Trials in HumansSunday May 4, 2025 / 12:30-13:30 Nationwide population-based cohort study on theuse and persistence of infliximab IV and SC inFrance: Riposte IBD study Poster Presentation #0014IMIBD_POS: IBD: Comparative Effectiveness StudiesTuesday May 6, 2025 / 12:30-13:30 Notes to Editors: About ZYMFENTRA® (infliximab-dyyb) ZYMFENTRA® (infliximab-dyyb) is a prescription medicine used as an injection under the skin (subcutaneous injection) by adults for the maintenance treatment of moderately-to-severely active ulcerative colitis following treatment with an infliximab product given by intravenous infusion (IV), Moderately-to-severely active Crohn's disease following treatment with an infliximab product given by intravenous infusion (IV). ZYMFENTRA blocks the action of tumor necrosis factor-alpha (TNF-alpha), a protein that can be overproduced in response to certain diseases and cause the immune system to attack normal, healthy parts of the body. ZYMFENTRA was approved by the FDA through the Biologics License Application (BLA) under the 351 (a) pathway of the Public Health Service Act (a "stand-alone" BLA). ZYMFENTRA is considered a new biologic with a first-approved subcutaneous administration form and thus will be under patent protection for its dosage form by 2037 and for its route of administration by 2040. Indication and Important Safety Information ZYMFENTRA® is a prescription medicine indicated in adults for maintenance treatment of: Moderately-to-severely active Crohn's disease following treatment with an infliximab product administered intravenously. Moderately-to-severely active ulcerative colitis following treatment with an infliximab product administered intravenously. It is not known if ZYMFENTRA is safe and effective in children under 18 years of age. What is the most important information I should know about ZYMFENTRA? SERIOUS INFECTIONS Patients treated with ZYMFENTRA are at increased risk for developing serious infections involving various organ systems and sites that may lead to hospitalization or death. Discontinue ZYMFENTRA if a patient develops a serious infection or sepsis.Reported infections include: Active tuberculosis (TB), including reactivation of latent TB. Patients frequently presented with disseminated or extrapulmonary disease. Patients should be tested for latent TB before and during treatment with ZYMFENTRA. Treatment for latent infection should be initiated prior to treatment with ZYMFENTRA. Invasive fungal infections, including histoplasmosis, coccidioidomycosis, candidiasis, aspergillosis, blastomycosis, and pneumocystosis. Patients may present with disseminated, rather than localized, disease. Empiric anti-fungal therapy should be considered in patients at risk for invasive fungal infections who develop severe systemic illness. Bacterial, viral, and other infections due to opportunistic pathogens, including Legionella and Listeria. The risks and benefits of treatment with ZYMFENTRA should be carefully considered prior to initiating therapy in patients with chronic or recurrent infection. Closely monitor patients for the development of signs and symptoms of infection during and after treatment with ZYMFENTRA, including the possible development of TB in patients who tested negative for latent TB infection prior to initiating therapy.Risk of infection may be higher in patients greater than 65 years of age, patients with comorbid conditions and/or patients taking concomitant immunosuppressant therapy. In clinical trials, other serious infections observed in patients treated with infliximab included arthritis bacterial, pneumonia, and urinary tract infection. MALIGNANCIES Malignancies, some fatal, have been reported in children, adolescents, and young adults treated with TNF blockers, including infliximab products. Approximately half of these cases were lymphomas, including Hodgkin's and non-Hodgkin's lymphoma. The other cases represented a variety of malignancies, including rare malignancies that are usually associated with immunosuppression and malignancies that are not usually observed in children and adolescents. The malignancies occurred after a median of 30 months after the first dose of therapy. Most of the patients were receiving concomitant immunosuppressants. Post-marketing cases of hepatosplenic T-cell lymphoma, a rare type of T-cell lymphoma, have been reported in patients treated with TNF blockers, including infliximab products. These cases have had a very aggressive disease course and have been fatal. The majority of reported cases have occurred in patients with Crohn's disease or ulcerative colitis, and most were in adolescent and young adult males. Almost all of these patients had received treatment with azathioprine or 6-mercaptopurine concomitantly with a TNF blocker at or prior to diagnosis. Carefully assess the risks and benefits of treatment with ZYMFENTRA, especially in these patient types. In clinical trials of all TNF blockers, more cases of malignancies were observed compared with controls and the expected rate in the general population. In clinical trials of some TNF blockers, including infliximab products, more cases of other malignancies were observed compared with controls. As the potential role of TNF blocker therapy in the development of malignancies is not known, caution should be exercised when considering treatment of patients with a current or a past history of malignancy. Melanoma and Merkel cell carcinoma have been reported in patients treated with TNF blocker therapy, including infliximab products. Periodic skin examination is recommended for all patients, particularly those with risk factors for skin cancer. CONTRAINDICATIONS ZYMFENTRA is contraindicated in patients with a previous severe hypersensitivity reaction to infliximab-dyyb, other infliximab products, any of the inactive ingredients of ZYMFENTRA or any murine proteins (severe hypersensitivity reactions have included anaphylaxis, hypotension and serum sickness). HEPATITIS B VIRUS REACTIVATION TNF blockers, including infliximab products, have been associated with reactivation of hepatitis B virus (HBV) in patients who are chronic carriers. Some cases were fatal. Patients should be tested for HBV infection before initiating ZYMFENTRA. For patients who test positive, consult a physician with expertise in the treatment of hepatitis B. Exercise caution when prescribing ZYMFENTRA for patients identified as carriers of HBV and monitor closely for active HBV infection during and following termination of therapy with ZYMFENTRA. Discontinue ZYMFENTRA in patients who develop HBV reactivation and initiate antiviral therapy with appropriate supportive treatment. Exercise caution when considering resumption of ZYMFENTRA and monitor patients closely. HEPATOTOXICITY Hepatobiliary disorders, including acute liver failure, jaundice abnormal hepatic function, hepatic steatosis, hepatitis, hepatotoxicity, hyperbilirubinemia and non-alcoholic fatty liver, have been reported in patients receiving infliximab products post-marketing. Some cases were fatal or required liver transplant. Aminotransferase elevations were not noted prior to discovery of liver injury in many cases. Patients with symptoms or signs of liver dysfunction should be evaluated for evidence of liver injury. If jaundice and/or marked liver enzyme elevations (eg, ≥5 times the upper limit of normal) develop, ZYMFENTRA should be discontinued and a thorough investigation of the abnormality should be undertaken. CONGESTIVE HEART FAILURE Cases of worsening congestive heart failure (CHF) and new onset CHF have been reported with TNF blockers. Some cases had a fatal outcome. In several exploratory trials of other TNF blockers in the treatment of CHF, there were greater proportions of TNF-blocker-treated patients who had CHF exacerbations requiring hospitalization or increased mortality. ZYMFENTRA has not been studied in patients with a history of CHF and ZYMFENTRA should be used with caution in patients with CHF. HEMATOLOGIC REACTION Cases of leukopenia, neutropenia, thrombocytopenia and pancytopenia (some fatal) have been reported. The causal relationship to infliximab-product therapy remains unclear. Exercise caution in patients who have ongoing or a history of significant hematologic abnormalities. Advise patients to seek immediate medical attention if they develop signs and symptoms of blood dyscrasias or infection. Consider discontinuation of ZYMFENTRA in patients who develop significant hematologic abnormalities. HYPERSENSITIVITY AND OTHER ADMINISTRATION REACTIONS In post-marketing experience, serious systemic hypersensitivity reactions (including anaphylaxis, hypotension and serum sickness) have been reported following administration of infliximab products. If an anaphylactic or other clinically significant hypersensitivity reaction occurs, institute appropriate therapy and discontinue ZYMFENTRA. INJECTION SITE REACTIONS In clinical studies, localized injection-site reactions were reported following administration of ZYMFENTRA. If a clinically significant injection-site reaction occurs, institute appropriate therapy and discontinue ZYMFENTRA. NEUROLOGIC REACTIONS Agents that inhibit TNF have been associated with central nervous system (CNS) manifestation of systemic vasculitis, seizure and new onset or exacerbation of CNS demyelinating disorders, including multiple sclerosis and optic neuritis and peripheral demyelinating disorders, including Guillain-Barré syndrome. Exercise caution when considering ZYMFENTRA in patients with these disorders and consider discontinuation if these disorders develop. RISK OF INFECTION WITH CONCURRENT ADMINISTRATION OF OTHER BIOLOGICS PRODUCTS Serious infections and neutropenia have been reported with concurrent use of ZYMFENTRA with other immunosuppressive biological products. The concurrent use of ZYMFENTRA with other immunosuppressive biological products used to treat UC and CD may increase the risk of infection and is not recommended. RISK OF ADDITIVE IMMUNOSUPPRESSIVE EFFECTS FROM PRIOR BIOLOGICAL PRODUCTS Consider the half-life and mode of action of prior biological products to avoid unintended additive immunosuppressive effects when initiating ZYMFENTRA. AUTOIMMUNITY Treatment with TNF blockers may result in the formation of autoantibodies and in the development of a lupus-like syndrome. Discontinue ZYMFENTRA treatment if symptoms of a lupus-like syndrome develop. VACCINATIONS AND USE OF LIVE VACCINES/THERAPEUTIC INFECTIOUS AGENTS Prior to initiating ZYMFENTRA, update vaccinations in accordance with current vaccination guidelines. Live vaccines or therapeutic infectious agents should not be given with ZYMFENTRA due to the possibility of clinical infections, including disseminated infections. At least a 6-month waiting period following birth is recommended before the administration of any live vaccine to infants exposed in utero to ZYMFENTRA. ADVERSE REACTIONS In clinical trials with ZYMFENTRA, the most common adverse reactions occurring in ≥3% of ZYMFENTRA-treated patients included site reactions, COVID-19, anemia, arthralgia, infection site reaction, increased alanine aminotransferase and abdominal pain for UC, and COVID-19, headache, upper respiratory tract infection, injection site reaction, diarrhea, increased blood creatine phosphokinase, arthralgia, increased alanine aminotransferase, hypertension, urinary tract infection, neutropenia, dizziness and leukopenia for CD. Please click for Full U.S. Prescribing Information. Globally, prescribing information varies; refer to the individual country product label for complete information. About Digestive Disease Week®Digestive Disease Week® (DDW) is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery. Jointly sponsored by the American Association for the Study of Liver Diseases (AASLD), the American Gastroenterological Association (AGA), the American Society for Gastrointestinal Endoscopy (ASGE) and the Society for Surgery of the Alimentary Tract (SSAT), DDW is an in-person and online meeting from May 3-6, 2025. The meeting showcases more than 5,600 abstracts and hundreds of lectures on the latest advances in GI research, medicine and technology. More information can be found at www.ddw.org About Celltrion, Inc.Celltrion is a leading biopharmaceutical company that specializes in researching, developing, manufacturing, marketing and sales of innovative therapeutics that improve people's lives worldwide. Celltrion is a pioneer in the biosimilar space, having launched the world's first monoclonal antibody biosimilar. Our global pharmaceutical portfolio addresses a range of therapeutic areas including immunology, oncology, hematology, ophthalmology and endocrinology. Beyond biosimilar products, we are committed to advancing our pipeline with novel drugs to push the boundaries of scientific innovation and deliver quality medicines. For more information, please visit our website www.celltrion.com/en-us. and stay updated with our latest news and events on our social media: LinkedIn, Instagram, X, and Facebook. About Celltrion USACelltrion USA is Celltrion's U.S. subsidiary established in 2018. Headquartered in New Jersey, Celltrion USA is committed to expanding access to innovative biologics to improve care for U.S. patients. Celltrion's FDA-approved biosimilar products in immunology, oncology, hematology, and endocrinology include: INFLECTRA® (infliximab-dyyb), TRUXIMA® (rituximab-abbs), HERZUMA® (trastuzumab-pkrb), VEGZELMA® (bevacizumab-adcd), YUFLYMA®(adalimumab-aaty), AVTOZMA® (tocilizumab-anho), STEQEYMA® (ustekinumab-stba), STOBOCLO® (denosumab-bmwo), OSENVELT® (denosumab-bmwo) and OMLYCLO® (omalizumab-igec), as well as the novel biologic ZYMFENTRA® (infliximab-dyyb). Celltrion USA will continue to leverage Celltrion's unique heritage in biotechnology, supply chain excellence and best-in-class sales capabilities to improve access to high-quality biopharmaceuticals for U.S. patients. For more information, please visit www.celltrionusa.com and stay updated with our latest news and events on our social media: LinkedIn. FORWARD-LOOKING STATEMENTCertain information set forth in this press release contains statements related to our future business and financial performance and future events or developments involving Celltrion, Inc. and its subsidiaries that may constitute forward-looking statements under pertinent securities laws. This press release contains forward looking statements. These statements may be also identified by words such as "prepares", "hopes to", "upcoming", "plans to", "aims to", "to be launched", "is preparing", "once gained", "could", "with the aim of", "may", "once identified", "will", "working towards", "is due", "become available", "has potential to", "anticipate" the negative of these words or such other variations thereon or comparable terminology. In addition, our representatives may make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Celltrion, Inc. and its subsidiaries' management, of which many are beyond its control. Forward-looking statements are provided to allow potential investors the opportunity to understand management's beliefs and opinions in respect of the future so that they may use such beliefs and opinions as one factor in evaluating an investment. These statements are not guarantees of future performance and undue reliance should not be placed on them. Such forward-looking statements necessarily involve known and unknown risks and uncertainties associated with the company's business, including the risk factors disclosed in its Annual Report and/or Quarterly Reports, which may cause actual performance and financial results in future periods to differ materially from any projections of future performance or results expressed or implied by such statements. Celltrion, Inc. and its subsidiaries undertake no obligation to update forward-looking statements if circumstances or management's estimates or opinions should change except as required by applicable securities laws.

YUFLYMA® (adalimumab-aaty) is a high-concentration (100mg/mL) and citrate-free formulation of Humira® (adalimumab) biosimilar, that is now interchangeable [1]Interchangeable designation of YUFLYMA® is supported by positive data from the Phase III interchangeability study in patients with moderate-to-severe plaque psoriasis INCHEON, South Korea, April 14, 2025 -- Celltrion, Inc. today announced that the U.S. Food and Drug Administration (FDA) has designated YUFLYMA® (adalimumab-aaty), as an interchangeable biosimilar to Humira® (adalimumab). YUFLYMA is an FDA-approved, high-concentration (100mg/mL) and citrate-free formulation of Humira® biosimilar, approved for multiple inflammatory indications.[1] "With this new designation, YUFLYMA is further positioned to help more patients gain access to and afford the therapy they need," said Thomas Nusbickel, Chief Commercial Officer at Celltrion USA. "YUFLYMA has the same dosage form, route of administration, and dosing regimen as the reference product. The pharmacist's ability to substitute the biosimilar directly at the pharmacy without the hassle of a new prescription and without the patient having to learn a new method of administration can be a game changer in increasing patient access to adalimumab." The interchangeable designation was supported by data from the Phase III interchangeability study, which demonstrated similar outcomes in terms of pharmacokinetics, efficacy, safety and immunogenicity in patients with moderately to severely active plaque psoriasis who received reference adalimumab (ADA) continuously and those who alternated between reference ADA and YUFLYMA during the dosing interval of Week 25-27. The result of the interchangeability study was presented at the European Academy of Dermatology & Venereology (EADV) 2024.[2]  FDA-approved interchangeable biosimilars may be substituted for the reference product at the pharmacy without the intervention of the prescribing health care provider, subject to state laws.[3] The high-concentration form of YUFLYMA was FDA-approved in May 2023 and is currently available as 20mg, 40 mg and 80mg solution for injection in a prefilled syringe and in an autoinjector pen. YUFLYMA was introduced into the US commercial market on July 2, 2023. YUFLYMA is available in two pricing options to help provide more affordable options for patients. Adalimumab-aaty, the unbranded version, is priced at an 85% discount to the current wholesale acquisition cost (WAC) list price of Humira (adalimumab), providing economic benefits for patients and overall healthcare system. The branded version is priced at a 5% discount to the current WAC of Humira (adalimumab). Notes to Editors: About YUFLYMA® (CT-P17, biosimilar adalimumab-aaty)[1] YUFLYMA is the world's first proposed high-concentration, low-volume and citrate-free adalimumab biosimilar to receive European Commission approval. YUFLYMA is FDA approved for the treatment of patients with rheumatoid arthritis, juvenile idiopathic arthritis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, ulcerative colitis, plaque psoriasis, hidradenitis suppurativa and uveitis. YUFLYMA has been designated by the FDA as an interchangeable biosimilar in a prefilled syringe. YUFLYMA is a recombinant fully human anti–tumor necrosis factor α (anti-TNFα) monoclonal antibody. YUFLYMA is available in 20mg/0.2mL, 40mg/0.4mL and 80mg/0.8mL. IMPORTANT SAFETY INFORMATION[1]This important safety information also applies to YUFLYMA® (adalimumab-aaty) SERIOUS INFECTIONS Patients treated with adalimumab-aaty are at increased risk for developing serious infections that may lead to hospitalization or death. Most patients who developed these infections were taking concomitant immunosuppressants such as methotrexate or corticosteroids. Discontinue adalimumab-aaty if a patient develops a serious infection or sepsis. Reported infections include: Active tuberculosis (TB), including reactivation of latent TB. Patients with TB have frequently presented with disseminated or extrapulmonary disease. Test patients for latent TB before adalimumab-aaty use and during therapy. Initiate treatment for latent TB prior to adalimumab-aaty use.Invasive fungal infections, including histoplasmosis, coccidioidomycosis, candidiasis, aspergillosis, blastomycosis, and pneumocystosis. Patients with histoplasmosis or other invasive fungal infections may present with disseminated, rather than localized, disease. Antigen and antibody testing for histoplasmosis may be negative in some patients with active infection. Consider empiric antifungal therapy in patients at risk for invasive fungal infections who develop severe systemic illness.Bacterial, viral, and other infections due to opportunistic pathogens, including Legionella and Listeria. Carefully consider the risks and benefits of treatment with adalimumab-aaty prior to initiating therapy in patients with chronic or recurrent infection. Monitor patients closely for the development of signs and symptoms of infection during and after treatment with adalimumab-aaty, including the possible development of TB in patients who tested negative for latent TB infection prior to initiating therapy. Treatment with adalimumab-aaty should not be initiated in patients with an active infection, including localized infections.Patients over 65 years of age, patients with co-morbid conditions and/or patients taking concomitant immunosuppressants (such as corticosteroids or methotrexate), may be at greater risk of infection. Discontinue adalimumab-aaty if a patient develops a serious infection or sepsis. For a patient who develops a new infection during treatment with adalimumab-aaty, closely monitor them, perform a prompt and complete diagnostic workup appropriate for an immunocompromised patient, and initiate appropriate antimicrobial therapy.Drug interactions with biologic products: In clinical studies in patients with RA, an increased risk of serious infections has been observed with the combination of TNF blockers with anakinra or abatacept, with no added benefit; therefore, use of adalimumab-aaty with abatacept or anakinra is not recommended in patients with RA. A higher rate of serious infections has also been observed in patients with RA treated with rituximab who received subsequent treatment with a TNF blocker. There is insufficient information regarding the concomitant use of adalimumab-aaty and other biologic products for the treatment of RA, PsA, AS, CD, UC, PS, and HS. Concomitant administration of adalimumab-aaty with other biologic DMARDs (e.g., anakinra and abatacept) or other TNF blockers is not recommended based upon the possible increased risk for infections and other potential pharmacological interactions. A higher rate of serious infections has been observed in RA patients treated with rituximab who received subsequent treatment with a TNF blocker. MALIGNANCY Lymphoma and other malignancies, some fatal, have been reported in children and adolescent patients treated with TNF blockers, including adalimumab products. Postmarketing cases of hepatosplenic T-cell lymphoma (HSTCL), a rare type of T-cell lymphoma, have been reported in patients treated with TNF blockers, including adalimumab products. These cases have had a very aggressive disease course and have been fatal. The majority of reported TNF blocker cases have occurred in patients with Crohn's disease or ulcerative colitis and the majority were in adolescent and young adult males. Almost all of these patients had received treatment with azathioprine or 6-mercaptopurine concomitantly with a TNF blocker at or prior to diagnosis. It is uncertain whether the occurrence of HSTCL is related to the use of a TNF blocker or a TNF blocker in combination with these other immunosuppressants. Consider the risks and benefits of TNF blocker treatment including adalimumab-aaty prior to initiating therapy in patients with a known malignancy other than a successfully treated non-melanoma skin cancer (NMSC), or when considering continuing a TNF blocker in patients who develop a malignancy.In controlled portions of clinical trials of some adalimumab products, more cases of malignancies have been observed compared to control-treated adult patients.Non-melanoma skin cancer (NMSC) was reported during clinical trials for patients treated with adalimumab products. During the controlled portions of 39 global adalimumab clinical trials in adult patients with RA, PsA, AS, CD, UC, PS, HS and UV, the rate (95% confidence interval) of NMSC was 0.8 (0.52, 1.09) per 100 patient-years among adalimumab-treated patients and 0.2 (0.10, 0.59) per 100 patient-years among control-treated patients. Examine all patients, particularly those with a medical history of prior prolonged immunosuppressant therapy or psoriasis patients with a history of PUVA treatment, for the presence of NMSC prior to and during treatment with adalimumab-aaty.In clinical trials of some adalimumab products, there was an approximately threefold higher rate of lymphoma than expected in the general U.S. population. Patients with RA and other chronic inflammatory diseases, particularly those with highly active disease and/or chronic exposure to immunosuppressant therapies, may be at a higher risk (up to severalfold) than the general population for the development of lymphoma, even in the absence of TNF blockers.Postmarketing cases of acute and chronic leukemia were reported with the use of a TNF blocker in RA and other indications. Approximately half of the postmarketing cases of malignancies in children, adolescents, and young adults receiving adalimumab were lymphomas; other cases represented a variety of different malignancies and included rare malignancies usually associated with immunosuppression and malignancies that are not usually observed in children and adolescents. HYPERSENSITIVITY Anaphylaxis and angioneurotic edema have been reported following administration of adalimumab products. If an anaphylactic or other serious allergic reaction occurs, immediately discontinue administration of adalimumab-aaty and institute appropriate therapy. HEPATITIS B VIRUS REACTIVATION Use of TNF blockers, including adalimumab-aaty, may increase the risk of reactivation of hepatitis B virus (HBV) in patients who are chronic carriers. In some instances, HBV reactivation occurring in conjunction with TNF blocker therapy has been fatal.Evaluate patients at risk for HBV infection for prior evidence of HBV infection before initiating TNF blocker therapy.Exercise caution in prescribing TNF blockers for patients identified as carriers of HBV and closely monitor such patients for clinical and laboratory signs of active HBV infection throughout therapy and for several months following termination of therapy.In patients who develop HBV reactivation, stop adalimumab-aaty and initiate effective antiviral therapy with appropriate supportive treatment. The safety of resuming TNF blocker therapy after HBV reactivation is controlled is not known. Therefore, exercise caution when considering resumption of adalimumab-aaty therapy in this situation and monitor patients closely. NEUROLOGIC REACTIONS Use of TNF blocking agents, including adalimumab products, has been associated with rare cases of new onset or exacerbation of clinical symptoms and/or radiographic evidence of central nervous system demyelinating disease, including multiple sclerosis (MS) and optic neuritis, and peripheral demyelinating disease, including Guillain-Barré syndrome.Exercise caution in considering the use of adalimumab-aaty in patients with preexisting or recent-onset central or peripheral nervous system demyelinating disorders; discontinuation of adalimumab-aaty should be considered if any of these disorders develop.There is a known association between intermediate uveitis and central demyelinating disorders. HEMATOLOGIC REACTIONS Rare reports of pancytopenia including aplastic anemia have been reported with TNF blocking agents.Adverse reactions of the hematologic system, including medically significant cytopenia, have been infrequently reported with adalimumab products.Consider discontinuation of adalimumab-aaty therapy in patients with confirmed significant hematologic abnormalities. HEART FAILURE Cases of worsening congestive heart failure (CHF) and new-onset CHF have been reported with TNF blockers. Cases of worsening CHF have also been observed with adalimumab products.Exercise caution when using adalimumab-aaty in patients who have heart failure and monitor them carefully. AUTOIMMUNITY Treatment with adalimumab products may result in the formation of autoantibodies and, rarely, in the development of a lupus-like syndrome. If a patient develops symptoms suggestive of a lupus-like syndrome following treatment with adalimumab-aaty, discontinue treatment. IMMUNIZATIONS Patients on adalimumab-aaty may receive concurrent vaccinations, except for live vaccines.It is recommended that pediatric patients, if possible, be brought up to date with all immunizations in agreement with current immunization guidelines prior to initiating adalimumab-aaty therapy.No data are available on the secondary transmission of infection by live vaccines in patients receiving adalimumab products.The safety of administering live or live-attenuated vaccines in infants exposed to adalimumab in utero is unknown. Risks and benefits should be considered prior to vaccinating (live or live-attenuated) exposed infants. ADVERSE REACTIONS The most common adverse reactions in adalimumab clinical trials (>10%) were: infections (e.g., upper respiratory, sinusitis), injection site reactions, headache, and rash. INDICATIONS Adalimumab-aaty is a tumor necrosis factor (TNF) blocker indicated for: Rheumatoid Arthritis (RA): reducing signs and symptoms, inducing major clinical response, inhibiting the progression of structural damage, and improving physical function in adult patients with moderately to severely active RAJuvenile Idiopathic Arthritis (JIA): reducing signs and symptoms of moderately to severely active polyarticular JIA in patients 2 years of age and olderPsoriatic Arthritis (PsA): reducing signs and symptoms, inhibiting the progression of structural damage, and improving physical function in adult patients with active PsAAnkylosing Spondylitis (AS): reducing signs and symptoms in adult patients with active ASCrohn's Disease (CD): treatment of moderately to severely active Crohn's disease in adults and pediatric patients 6 years of age and olderUlcerative Colitis (UC): treatment of moderately to severely active ulcerative colitis in adultsLimitations of Use: Effectiveness has not been established in patients who have lost response to or were intolerant to TNF blockersPlaque Psoriasis (Ps): treatment of adult patients with moderate to severe chronic plaque psoriasis who are candidates for systemic therapy or phototherapy, and when other systemic therapies are medically less appropriateHidradenitis Suppurativa (HS): treatment of adult patients with moderate to severe hidradenitis suppurativaUveitis (UV): treatment of non-infectious intermediate, posterior, and panuveitis in adult patients For Yuflyma (adalimumab-aaty): Please click for Full U.S. Prescribing Information. For adalimumab-aaty: Please see Full U.S. Prescribing Information. Globally, prescribing information varies; refer to the individual country product label for complete information. About Celltrion, Inc. Celltrion is a leading biopharmaceutical company that specializes in researching, developing, manufacturing, marketing and sales of innovative therapeutics that improve people's lives worldwide. Celltrion is a pioneer in the biosimilar space, having launched the world's first monoclonal antibody biosimilar. Our global pharmaceutical portfolio addresses a range of therapeutic areas including immunology, oncology, hematology, ophthalmology and endocrinology. Beyond biosimilar products, we are committed to advancing our pipeline with novel drugs to push the boundaries of scientific innovation and deliver quality medicines. For more information, please visit our website www.celltrion.com/en-us and stay updated with our latest news and events on our social media: LinkedIn, Instagram, X, and Facebook. About Celltrion USA Celltrion USA is Celltrion's U.S. subsidiary established in 2018. Headquartered in New Jersey, Celltrion USA is committed to expanding access to innovative biologics to improve care for U.S. patients. Celltrion's FDA-approved biosimilar products in immunology, oncology, hematology, and endocrinology include: INFLECTRA® (infliximab-dyyb), TRUXIMA® (rituximab-abbs), HERZUMA® (trastuzumab-pkrb), VEGZELMA® (bevacizumab-adcd), YUFLYMA®(adalimumab-aaty), AVTOZMA® (tocilizumab-anho), STEQEYMA® (ustekinumab-stba), STOBOCLO® (denosumab-bmwo), OSENVELT® (denosumab-bmwo) and OMLYCLO® (omalizumab-igec), as well as the novel biologic ZYMFENTRA® (infliximab-dyyb). Celltrion USA will continue to leverage Celltrion's unique heritage in biotechnology, supply chain excellence and best-in-class sales capabilities to improve access to high-quality biopharmaceuticals for U.S. patients. For more information, please visit www.celltrionusa.com and stay updated with our latest news and events on our social media: LinkedIn. FORWARD-LOOKING STATEMENT Certain information set forth in this press release contains statements related to our future business and financial performance and future events or developments involving Celltrion, Inc. and its subsidiaries that may constitute forward-looking statements under pertinent securities laws. This press release contains forward looking statements. These statements may be also identified by words such as "prepares", "hopes to", "upcoming", "plans to", "aims to", "to be launched", "is preparing", "once gained", "could", "with the aim of", "may", "once identified", "will", "working towards", "is due", "become available", "has potential to", "anticipate" the negative of these words or such other variations thereon or comparable terminology.In addition, our representatives may make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Celltrion, Inc. and its subsidiaries' management, of which many are beyond its control.Forward-looking statements are provided to allow potential investors the opportunity to understand management's beliefs and opinions in respect of the future so that they may use such beliefs and opinions as one factor in evaluating an investment. These statements are not guarantees of future performance and undue reliance should not be placed on them.Such forward-looking statements necessarily involve known and unknown risks and uncertainties associated with the company's business, including the risk factors disclosed in its Annual Report and/or Quarterly Reports, which may cause actual performance and financial results in future periods to differ materially from any projections of future performance or results expressed or implied by such statements.Celltrion, Inc. and its subsidiaries undertake no obligation to update forward-looking statements if circumstances or management's estimates or opinions should change except as required by applicable securities laws. Trademarks Humira is a registered trademark of AbbVie. YUFLYMA® is a registered trademark of Celltrion, Inc., used under license. References [1] YUFLYMA US prescribing information (2023) [2] Lebwohl M et al., Pharmacokinetics, Efficacy and Safety after Multiple Switches from Reference Adalimumab to Adalimumab Biosimilar (CT-P17) in comparison with the Maintenance Group (Reference Adalimumab) in Patients with Moderate-toSevere Plaque Psoriasis: Week 27 Results from the Phase III Interchangeability Study. [EADV 2024, Poster number P0931]. Available at: https://s3.eu-central-1.amazonaws.com/m-anage.com.storage.eadv/abstracts_congress_2024/41489.pdf [3] 9 Things to Know About Biosimilars and Interchangeable Biosimilars. Available at : https://www.fda.gov/drugs/things-know-about/9-things-know-about-biosimilars-and-interchangeable-biosimilars

STEQEYMA® (ustekinumab-stba) is Celltrion's biosimilar to STELARA® (ustekinumab), which was launched on March 12, 2025Celltrion's adalimumab-aaty was previously added to the Costco Member Prescription Program in August 2024 JERSEY CITY, N.J., March 27, 2025 - Celltrion, Inc., today announced that STEQEYMA® (ustekinumab-stba), a biosimilar to STELARA® (ustekinumab) has been added to the Costco Member Prescription Program. "We're focused on improving affordability and access to a widely used, high-cost treatment for a variety of inflammatory conditions," said Francine Galante, Vice President of Market Access at Celltrion USA. "The addition of STEQEYMA to the Costco Member Prescription Program together with adalimumab-aaty will help us deliver our commitment to lowering financial barriers and improving access to critical treatments." STEQEYMA is available in both subcutaneous injection and intravenous infusion and is indicated for the treatment of plaque psoriasis (PsO) and psoriatic arthritis (PsA) in adult and pediatric patients, as well as Crohn's disease (CD) and ulcerative colitis (UC) in adult patients. The Costco Member Prescription Program is a prescription drug discount card program offered by Costco Health Solutions that provides eligible Costco members and their eligible dependents the ability to obtain lower prices on STEQEYMA and other participating drugs at Costco Specialty Pharmacies and at participating pharmacies.  "By partnering with Costco Health Solutions once again, we are able to help even more Americans lower the price of their prescriptions, given the fact that Stelara ranks as one of the most expensive prescription drugs on the market," said Tom Nusbickel, Chief Commercial Officer at Celltrion USA. STEQEYMA will be available in the U.S. from Costco Specialty Pharmacies on April 1st, 2025, for self-funded employer plans and Costco members who are uninsured and want to pay cash for their STEQEYMA prescription or who have been denied coverage by their insurers. Notes to Editors: About STEQEYMA® (ustekinumab-stba)STEQEYMA®, formerly known as CT-P43, is a human IL-12 and -23 antagonist indicated for multiple immune-mediated diseases. It encompasses all indications approved for the STELARA® reference product, including psoriasis (PsO), psoriatic arthritis (PsA), Crohn's disease (CD), ulcerative colitis (UC) in adults, and PsO and PsA in pediatric patients 6 years of age and older. STEQEYMA is available in both subcutaneous and intravenous formulations. The subcutaneous injection comes in two strengths: 45mg/0.5 mL or 90mg/1 mL solution in a single-dose, prefilled syringe. The intravenous infusion is provided as a 130mg/26 mL (5mg/mL) solution in a single-dose vial. INDICATIONSSTEQEYMA® (ustekinumab-stba) is indicated for the treatment of:Plaque Psoriasis (PsO) in adults and pediatric patients 6 years of age and older with moderate to severe plaque psoriasis who are candidates for phototherapy or systemic therapy.Psoriatic Arthritis (PsA) in adults and pediatric patients 6 years of age and older with active psoriatic arthritis.Crohn's Disease (CD) in adult patients with moderately to severely active Crohn's disease.Ulcerative Colitis (UC) in adult patients with moderately to severely active ulcerative colitis. IMPORTANT SAFETY INFORMATIONSTEQEYMA® is contraindicated in patients with clinically significant hypersensitivity to ustekinumab products or to any of the excipients in STEQEYMA.Serious infections have occurred. Avoid starting STEQEYMA during any clinically important active infection. If a serious or clinically significant infection develops, discontinue STEQEYMA until the infection resolves.Serious infections from mycobacteria, salmonella, and BCG vaccinations have been reported in patients genetically deficient in IL-12/IL-23. Consider diagnostic tests for these infections as dictated by clinical circumstances.Evaluate patients for TB prior to starting STEQEYMA. Initiate treatment of latent TB before administering STEQEYMA.Ustekinumab products may increase risk of malignancy. The safety of ustekinumab products in patients with a history of or a known malignancy has not been evaluated. Monitor all patients receiving STEQEYMA for signs of malignancies.If an anaphylactic or other clinically significant hypersensitivity reaction occurs, institute appropriate therapy and discontinue STEQEYMA.If Posterior Reversible Encephalopathy Syndrome (PRES) is suspected, treat promptly and discontinue STEQEYMA.Avoid use of live vaccines in patients during treatment with STEQEYMA. Non-live vaccinations received during STEQEYMA treatment may not elicit enough immune response to prevent disease.If diagnosis of noninfectious pneumonia is confirmed, discontinue STEQEYMA and institute appropriate treatment.The most common adverse reactions (≥3%) reported in patients receiving ustekinumab were:Psoriasis: nasopharyngitis, upper respiratory tract infection, headache, and fatigue.CD: vomiting, nasopharyngitis, injection site erythema, vulvovaginal candidiasis/mycotic infection, bronchitis, pruritus, urinary tract infection, and sinusitis.UC: nasopharyngitis, headache, abdominal pain, influenza, fever, diarrhea, sinusitis, fatigue, and nausea. For more information, see Full Prescribing Information. About CelltrionCelltrion is a leading biopharmaceutical company that specializes in researching, developing, manufacturing, marketing and sales of innovative therapeutics that improve people's lives worldwide. Celltrion is a pioneer in the biosimilar space, having launched the world's first monoclonal antibody biosimilar. Our global pharmaceutical portfolio addresses a range of therapeutic areas including immunology, oncology, hematology, ophthalmology and endocrinology. Beyond biosimilar products, we are committed to advancing our pipeline with novel drugs to push the boundaries of scientific innovation and deliver quality medicines. For more information, please visit our website www.celltrion.com/en-us. and stay updated with our latest news and events on our social media: LinkedIn, Instagram, X, and Facebook. About Celltrion USACelltrion USA is Celltrion's U.S. subsidiary established in 2018. Headquartered in New Jersey, Celltrion USA is committed to expanding access to innovative biologics to improve care for U.S. patients. Celltrion currently has ten biosimilars approved by the U.S. FDA: INFLECTRA® (infliximab-dyyb), TRUXIMA® (rituximab-abbs), HERZUMA® (trastuzumab-pkrb), VEGZELMA® (bevacizumab-adcd), YUFLYMA®(adalimumab-aaty), AVTOZMA® (tocilizumab-anho), STEQEYMA® (Ustekinumab-stba) STOBOCLO® (denosumab-bmwo), OSENVELT® (denosumab-bmwo), and OMLYCLO® (omalizumab-igec) as well as a novel biologic ZYMFENTRA® (infliximab-dyyb). Celltrion USA will continue to leverage Celltrion's unique heritage in biotechnology, supply chain excellence and best-in-class sales capabilities to improve access to high-quality biopharmaceuticals for U.S. patients. For more information, please visit www.celltrionusa.com and stay updated with our latest news and events on our social media: LinkedIn. FORWARD-LOOKING STATEMENTCertain information set forth in this press release contains statements related to our future business and financial performance and future events or developments involving Celltrion Inc. and its subsidiaries that may constitute forward-looking statements, under pertinent securities laws. These statements may be also identified by words such as "prepares", "hopes to", "upcoming", "plans to", "aims to", "to be launched", "is preparing", "once gained", "could", "with the aim of", "may", "once identified", "will", "working towards", "is due", "become available", "has potential to", the negative of these words or such other variations thereon or comparable terminology. In addition, our representatives may make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Celltrion Inc. and its subsidiaries' management, of which many are beyond its control. Forward-looking statements are provided to allow potential investors the opportunity to understand management's beliefs and opinions in respect to the future so that they may use such beliefs and opinions as one factor in evaluating an investment. These statements are not guarantees of future performance and undue reliance should not be placed on them. Such forward-looking statements necessarily involve known and unknown risks and uncertainties associated with the company's business, including the risk factors disclosed in its Annual Report and/or Quarterly Reports, which may cause actual performance and financial results in future periods to differ materially from any projections of future performance or results expressed or implied by such statements.Celltrion Inc. and its subsidiaries undertake no obligation to update forward-looking statements if circumstances or management's estimates or opinions should change except as required by applicable securities laws. TrademarksSTELARA® is a registered trademark of Johnson & Johnson.STEQEYMA® is a registered trademark of Celltrion, Inc., used under license.